The macrostructure of alloy steel forgings such as gear blanks, crank-shafts and connecting rods is considered very important, as it has direct relation to their mechanical properties and is much influenced by their ingot structures and the manners of workings. Especially it is much influenced by the manners of heating before forging.
The results of systematic studies on forging and heating of the fundamental types are described in the present paper, as follows:
I Introduction.
II The change of macrostructure of billets by pre-heating of ingots.
III The relation between the change of macrogtructure of ingots and the manner of working.
IV Some examples of macrostructure in forgings such as gear blanks and cylinders.
V Conclusion.

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A rolling mill engineer under the present situation should meet the increasing demand for steel products. It is necessary therefore for him to investigate into how rolling should be done so that every roling products might be sound and free from defects and made on the paying and commercial scale. Being based on the results of experimental researches at some large bar mills for the past seventeen years, the present paper intented to explain how much influence is exerted on the rolling mill eapacity by different shapes of roll calibres and decreased numbers of rolling passes. It is also shown that the rolling velocity of a large bar mill is almost equal to that of a blooming mill. Consequently it is possible to raise the efficiency by increasing the unit weight of rolling billets.

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